As in the rest of the subseries, the setting of The Convergence is our Solar System in the, by now fairly far, future: the late twenty-seventh century, about three-quarters of a century after the events of The Legion. The main and point-of-view character is presumably still Alice Hansen, also known as Alatumbra, by now by far almost certainly the oldest woman alive, a mage and diplomat still active as the liaison between the nations of Earth and the interuniversal alliance that has defended Earth in the past.

The tentative logline for The Convergence is:

When several enemy fleets converge on Earth, Alice Hansen must organize the system’s defenses to repel them.

While the period before the events of the previous volume was largely peaceful, the years from then until this story have been much less so. After a civil war in the independent colony on Mars, several Earth nations and independent colonies fight the Second Belt War, and then two decades later the nations of Earth fight, unsuccessfully, to keep their interstellar colonies, some of which have founded their own colonies.

In the aftermath of the War of Secession, Alice Hansen receives news from various contacts of several different fleets from or allied to the Dragon Empire flying toward Earth’s solar system, in large enough numbers that any uncoordinated defense is not likely to succeed.

She has little formal authority, but uses it and calls in or begs favors to organize a meeting of representatives of the various nations of Earth and the astrographically closest colonies, and begs for their help defending Earth. With the political situation so fraught, her news and request provokes heated and extended argument, but little result, so she asks for help from her Alliance contacts, and the Shine and Wild Empire and Elvida send delegations and a first fleet of ships. When these arrive, they lend enough weight that most of the assembled representative agree to cooperate and help defend Earth.

But the negotiations took so long that just after the Earth-, Mars- and Belt-based fleets launch toward the rendezvous points, and just after the interstellar colonies’ forces enter the system, at least four enemy fleets also arrive, forcing the defenders to scramble to engage them. Alice Hansen, an experienced veteran of space combat, had hoped and expected to take part, but finds that she has to remain behind to coordinate.

The defending fleets manage to divert the enemy fleets away from the system’s inhabited worlds (Earth, Mars, Venus, maybe some gas giant moons, several smaller bodies in and around the Asteroid Belt, and stations at Lagrange Points) and well-trafficked routes, then begin maneuvers to hold them more or less in place and away from those tempting targets with fewer ships each. Once these maneuvers have begun, so that a substantial part of the combined fleet is freed up, these ships gather into one group and move from one enemy fleet to apply the concentration of force to destroy each in turn.